Unfortunately "correcthorsebatterystaple" is too long. https://xkcd.com/936/ https://xkcd.com/936/ ... but if the constraints are 4-20 alphanumeric characters

Unfortunately "correcthorsebatterystaple" is too long. https://xkcd.com/936/ https://xkcd.com/936/ ... but if the constraints are 4-20 alphanumeric characters case-insensitive pronounceable, then a sequence of words would work great.